quickpath 0.9.3

Easy access to elements of collection/object structures

QuickPath

QuickPath is a package, which provides functions for easy access the elements of collection/object structures.

Motivating example

animals = [
  {
    'name': 'Wombat', 
    'avg_properties': {
      'height': {'value': 66, 'unit': 'cm'}, 
      'length':{'value': 108, 'unit': 'cm'},
      'weight': {'value': 27, 'unit': 'kg'}
    }
  },
  {
    'name': 'Duck', 
    'avg_properties': {
      'height': {'value': 62, 'unit': 'cm'}, 
      'weight': {'value': 1, 'unit': 'kg'}
    }
  },
  {
    'name': 'Dog', 
    'max_properties': {
      'height': {'value': 95, 'unit': 'cm'}, 
      'weight': {'value': 105, 'unit': 'kg'}
    }
  },
]

Let's query that above structure:

for animal in animals:
  print(animal["name"], 
        'average length', 
        animal["avg_properties"]["length"]["value"])

This code will abort with error as no the Duck has no length key. We have to add one more check.

for animal in animals:
  print(animal["name"], 
        'average length', 
        animal["avg_properties"]["length"]["value"] 
          if "length" in animal["avg_properties"] 
          else '-')

This improved code will still fail as Dog has only max_property key, we have to handle this situation too.

for animal in animals:
  if "avg_properties" in animal 
      and "length" in animal["avg_properties"]:
    print(animal["name"], 
          'average length', 
          animal["avg_properties"]["length"]["value"])
  else:
    print(animal["name"], 
          'avarage length', 
          "-")

The above scenarios can be simplified by quickpath:

from quickimport import getpath
for animal in animals:
  print(animal["name"], 
        'average length', 
        getpath(animal, 
                ("avg_properties", "length", "value"), 
                default='-'))

Alternatively, the keys can be represented as a single string:

from quickimport import getpaths
for animal in animals:
  print(animal["name"], 
        'average length', 
        getpaths(animal, 
                "avg_properties.length.value"), 
                default='-'))

Separator can be changed to any alternative characters:

from quickimport import getpaths
for animal in animals:
  print(animal["name"], 
        'average length', 
        getpaths(animal, 
                "avg_properties/length/value"), 
                default='-', 
                sep='/')